Bug 1451455 - Fire the 'load' event on out-of-process iframes, r=rhunt

This is done by sending a message over PBrowser and PBrowserBridge when the
event would fire to fire it in the correct process.

Differential Revision: https://phabricator.services.mozilla.com/D33083

--HG--
extra : moz-landing-system : lando

dom/base/nsGlobalWindowInner.cpp

@@ -261,6 +261,7 @@
 #include "mozilla/dom/ClientState.h"
 
 #include "mozilla/dom/WindowGlobalChild.h"
+#include "mozilla/dom/BrowserChild.h"
 
 #include "mozilla/net/CookieSettings.h"
 
@@ -1917,6 +1918,54 @@ bool nsGlobalWindowInner::DialogsAreBeingAbused() {
   return false;
 }
 
+void nsGlobalWindowInner::FireFrameLoadEvent(bool aIsTrusted) {
+  // If we're not in a content frame, or are at a BrowsingContext tree boundary,
+  // such as the content-chrome boundary, don't fire the "load" event.
+  if (!GetBrowsingContext()->GetParent() ||
+      !GetBrowsingContext()->IsContent()) {
+    return;
+  }
+
+  // If embedder is same-process, fire the event on our embedder element.
+  //
+  // XXX: Bug 1440212 is looking into potentially changing this behaviour to act
+  // more like the remote case when in-process.
+  RefPtr<Element> element = GetBrowsingContext()->GetEmbedderElement();
+  if (element) {
+    nsEventStatus status = nsEventStatus_eIgnore;
+    WidgetEvent event(aIsTrusted, eLoad);
+    event.mFlags.mBubbles = false;
+    event.mFlags.mCancelable = false;
+
+    // Most of the time we could get a pres context to pass in here,
+    // but not always (i.e. if this window is not shown there won't
+    // be a pres context available). Since we're not firing a GUI
+    // event we don't need a pres context anyway so we just pass
+    // null as the pres context all the time here.
+    EventDispatcher::Dispatch(element, nullptr, &event, nullptr, &status);
+    return;
+  }
+
+  // We don't have an in-process embedder. Try to get our `BrowserChild` actor
+  // to send a message to that embedder. We want to double-check that our outer
+  // window is actually the one at the root of this browserChild though, just in
+  // case.
+  RefPtr<BrowserChild> browserChild =
+      BrowserChild::GetFrom(static_cast<nsPIDOMWindowInner*>(this));
+  if (browserChild) {
+    // Double-check that our outer window is actually at the root of this
+    // `BrowserChild`, in case we're in an odd maybe-unhosted situation like a
+    // print preview dialog.
+    nsCOMPtr<nsPIDOMWindowOuter> rootOuter =
+        do_GetInterface(browserChild->WebNavigation());
+    if (!rootOuter || rootOuter != GetOuterWindow()) {
+      return;
+    }
+
+    mozilla::Unused << browserChild->SendFireFrameLoadEvent(aIsTrusted);
+  }
+}
+
 nsresult nsGlobalWindowInner::PostHandleEvent(EventChainPostVisitor& aVisitor) {
   // Return early if there is nothing to do.
   switch (aVisitor.mEvent->mMessage) {
@@ -1977,25 +2026,7 @@ nsresult nsGlobalWindowInner::PostHandleEvent(EventChainPostVisitor& aVisitor) {
 
     mTimeoutManager->OnDocumentLoaded();
 
-    nsCOMPtr<Element> element = GetOuterWindow()->GetFrameElementInternal();
-    nsIDocShell* docShell = GetDocShell();
-    if (element && GetParentInternal() && docShell &&
-        docShell->ItemType() != nsIDocShellTreeItem::typeChrome) {
-      // If we're not in chrome, or at a chrome boundary, fire the
-      // onload event for the frame element.
-
-      nsEventStatus status = nsEventStatus_eIgnore;
-      WidgetEvent event(aVisitor.mEvent->IsTrusted(), eLoad);
-      event.mFlags.mBubbles = false;
-      event.mFlags.mCancelable = false;
-
-      // Most of the time we could get a pres context to pass in here,
-      // but not always (i.e. if this window is not shown there won't
-      // be a pres context available). Since we're not firing a GUI
-      // event we don't need a pres context anyway so we just pass
-      // null as the pres context all the time here.
-      EventDispatcher::Dispatch(element, nullptr, &event, nullptr, &status);
-    }
+    FireFrameLoadEvent(aVisitor.mEvent->IsTrusted());
 
     if (mVREventObserver) {
       mVREventObserver->NotifyAfterLoad();
@@ -7083,6 +7114,7 @@ nsPIDOMWindowInner::nsPIDOMWindowInner(nsPIDOMWindowOuter* aOuterWindow)
       mNumOfOpenWebSockets(0),
       mEvent(nullptr) {
   MOZ_ASSERT(aOuterWindow);
+  mBrowsingContext = aOuterWindow->GetBrowsingContext();
 }
 
 void nsPIDOMWindowInner::RegisterReportingObserver(ReportingObserver* aObserver,

dom/base/nsGlobalWindowInner.h

@@ -1197,6 +1197,9 @@ class nsGlobalWindowInner final : public mozilla::dom::EventTarget,
   // activation flag.
   bool ShouldResetBrowsingContextUserGestureActivation();
 
+  // Try to fire the "load" event on our content embedder if we're an iframe.
+  void FireFrameLoadEvent(bool aIsTrusted);
+
  public:
   // Dispatch a runnable related to the global.
   virtual nsresult Dispatch(mozilla::TaskCategory aCategory,

dom/base/nsPIDOMWindow.h

@@ -388,6 +388,11 @@ class nsPIDOMWindowInner : public mozIDOMWindow {
    */
   inline nsIDocShell* GetDocShell() const;
 
+  /**
+   * Get the browsing context in this window.
+   */
+  inline mozilla::dom::BrowsingContext* GetBrowsingContext() const;
+
   /**
    * Call this to indicate that some node (this window, its document,
    * or content in that document) has a paint event listener.
@@ -627,6 +632,8 @@ class nsPIDOMWindowInner : public mozIDOMWindow {
 
   RefPtr<mozilla::dom::TabGroup> mTabGroup;
 
+  RefPtr<mozilla::dom::BrowsingContext> mBrowsingContext;
+
   // A unique (as long as our 64-bit counter doesn't roll over) id for
   // this window.
   uint64_t mWindowID;

dom/base/nsPIDOMWindowInlines.h

@@ -72,6 +72,10 @@ mozilla::dom::BrowsingContext* nsPIDOMWindowOuter::GetBrowsingContext() const {
   return mBrowsingContext;
 }
 
+mozilla::dom::BrowsingContext* nsPIDOMWindowInner::GetBrowsingContext() const {
+  return mBrowsingContext;
+}
+
 mozilla::dom::Element* nsPIDOMWindowOuter::GetFocusedElement() const {
   return mInnerWindow ? mInnerWindow->GetFocusedElement() : nullptr;
 }

dom/html/test/test_ignoreuserfocus.html

@@ -44,10 +44,14 @@
         iframe.setAttribute("ignoreuserfocus", "true");
         iframe.setAttribute("height", "300px");
 
-        iframe.addEventListener('load', function (e) {
+        iframe.addEventListener('mozbrowserloadend', function (e) {
           // Get privileged iframe because mozbrowser iframe is not same origin
           // with the parent. We need to access its content through the wrapper.
           var privilegedIframe = SpecialPowers.wrap(iframe);
+          if (!privilegedIframe.contentWindow.location.href.endsWith("file_ignoreuserfocus.html")) {
+            return;
+          }
+
           privilegedIframe.contentWindow.addEventListener("MozAfterPaint", function(e) {
             privilegedIframe.contentWindow.addEventListener("focus",
               function(e) {

dom/ipc/BrowserBridgeChild.cpp

@@ -140,6 +140,23 @@ BrowserBridgeChild::RecvSetEmbeddedDocAccessibleCOMProxy(
   return IPC_OK();
 }
 
+mozilla::ipc::IPCResult BrowserBridgeChild::RecvFireFrameLoadEvent(
+    bool aIsTrusted) {
+  RefPtr<Element> owner = mFrameLoader->GetOwnerContent();
+  if (!owner) {
+    return IPC_OK();
+  }
+
+  // Fire the `load` event on our embedder element.
+  nsEventStatus status = nsEventStatus_eIgnore;
+  WidgetEvent event(aIsTrusted, eLoad);
+  event.mFlags.mBubbles = false;
+  event.mFlags.mCancelable = false;
+  EventDispatcher::Dispatch(owner, nullptr, &event, nullptr, &status);
+
+  return IPC_OK();
+}
+
 void BrowserBridgeChild::ActorDestroy(ActorDestroyReason aWhy) {
   mIPCOpen = false;
 }

dom/ipc/BrowserBridgeChild.h

@@ -83,6 +83,8 @@ class BrowserBridgeChild : public PBrowserBridgeChild {
   mozilla::ipc::IPCResult RecvSetEmbeddedDocAccessibleCOMProxy(
       const IDispatchHolder& aCOMProxy);
 
+  mozilla::ipc::IPCResult RecvFireFrameLoadEvent(bool aIsTrusted);
+
   void ActorDestroy(ActorDestroyReason aWhy) override;
 
  private:

dom/ipc/BrowserParent.cpp

@@ -3699,6 +3699,17 @@ mozilla::ipc::IPCResult BrowserParent::RecvGetSystemFont(nsCString* aFontName) {
   return IPC_OK();
 }
 
+mozilla::ipc::IPCResult BrowserParent::RecvFireFrameLoadEvent(bool aIsTrusted) {
+  BrowserBridgeParent* bridge = GetBrowserBridgeParent();
+  if (!bridge) {
+    NS_WARNING("Received `load` event on unbridged BrowserParent!");
+    return IPC_OK();
+  }
+
+  Unused << bridge->SendFireFrameLoadEvent(aIsTrusted);
+  return IPC_OK();
+}
+
 NS_IMETHODIMP
 FakeChannel::OnAuthAvailable(nsISupports* aContext,
                              nsIAuthInformation* aAuthInfo) {

dom/ipc/BrowserParent.h

@@ -765,6 +765,8 @@ class BrowserParent final : public PBrowserParent,
   mozilla::ipc::IPCResult RecvQueryVisitedState(
       InfallibleTArray<URIParams>&& aURIs);
 
+  mozilla::ipc::IPCResult RecvFireFrameLoadEvent(bool aIsTrusted);
+
  private:
   void SuppressDisplayport(bool aEnabled);
 

dom/ipc/PBrowser.ipdl

@@ -663,6 +663,11 @@ parent:
     sync SetPrefersReducedMotionOverrideForTest(bool aValue);
     sync ResetPrefersReducedMotionOverrideForTest();
 
+    /**
+     * Fire a `load` event on this PBrowser's embedding frame element.
+     */
+    async FireFrameLoadEvent(bool aIsTrusted);
+
 child:
     /**
      * Notify the remote browser that it has been Show()n on this

dom/ipc/PBrowserBridge.ipdl

@@ -51,6 +51,11 @@ child:
    */
   async SetEmbeddedDocAccessibleCOMProxy(IDispatchHolder aCOMProxy);
 
+  /**
+   * Fire a `load` event on this PBrowserBridge's embedding frame element.
+   */
+  async FireFrameLoadEvent(bool aIsTrusted);
+
 parent:
   // Destroy the remote web browser due to the nsFrameLoader going away.
   async __delete__();